DE69831458T2 - MID-POINT STEREO REPRODUCTION SYSTEM FOR MUSICAL INSTRUMENTS - Google Patents

Description

FIELD OF THE INVENTION

The The present invention relates to the field of electronic musical instruments, and more particularly, it relates to equipment for producing stereo sound effects through a centrally located speaker system, with extra high benefit for Live Presentations by players of electronic keyboards and electronic guitars.

STATE OF TECHNOLOGY

Although Stereo sound for the sound reproduction now finds worldwide recognition, uses the exploitation of stereo effects in the field of enhanced live music performances by soloists and small groups or bands not yet existing Potential, although many of the artists Use instruments that can produce stereo output signals which could potentially improve the overall impact of the music presentation.

at the conventional one Implementation for musical lectures be in stereo sound for usually two spatial separate speaker units at or near opposite ends the stage or the corners of the room, and each one Speaker is driven with a special amplifier, i. with right and left channels. The physical separation of the two speaker units is decisive, dependent environmental conditions such as the size and shape of the listener's room, the arrangement of the audience, Etc.

The excessive physical Separation destroyed the imaging performance, i. the "focus" of the origin of a sound image produced by a listener is perceived as e.g. an announcer, a soloist or a singer or a singer, who is on a central stage, where it is for the two staggered speaker units is the hardest, a focused to "synthesize" the central picture.

on the other hand benefits one insufficient spatial Although separation of the central figure, but they are the spatial Figure degrades, i. the ability to generate one from listeners perceived panoramic "Tonbühne", which is about the entire width extends.

In In practice, the limited physical distance chosen as "optimal" necessarily a compromise in which both the figure as well as the spatial reproduction or Figure suffer. This "optimal" separation can for listeners who in proportion to the speaker units located in a central location, acceptable Deliver results. Located in most rooms or concert halls However, some listeners too close to one of the speaker units, so the respective, closer arranged Channel dominates; not only the stereo effect can be lost go, in many cases Also, the perception of the music overall may be inferior leave in comparison to a monophonic reproduction of the same Music. In situations where the musician made a lot of space Would like to create a stereo effect can be a listener with a fine ear at an unbalanced listening position the lecture as disturbing or even feel absolutely unacceptable. The missing balance bothers too the musician when he is too close to one of the stereo speaker units located.

If the musician or sound engineer tries to mitigate this problem by: the two speaker units positioned closer to each other or through the use of a commercially available "combo amp" unit with integrated front-facing and side-by-side stereo speakers, in a common housing with the amplifier are arranged and thereby have a very small spatial separation, this is at the expense of the desired effect of the stereo effect against, even for all listeners completely can be lost if the speakers are so close together that are practically monophonic.

While many Keyboarders and guitarists develop special stereo effects during rehearsals can and in this regard no effort in recording shy away, the musicians are rather reluctant to ambivalences at live lectures or Disputes regarding the arrangement of stereo speakers too avoid, and do not necessarily put up with full commitment for an excellent Stereo power, but give up with a substantially satisfied with a monophonic speaker arrangement, such as with a compact Placement or a stack of speaker units or the "stereo" speakers with minimal spacing in a "combo amp" unit, though this may be true for the audience overall lead to a perception of a more uniform coverage whereby However, this is significantly at the expense of the potential improvement that effective stereo effects can give live lectures.

In the basic stereo recording modes, an orchestra can be recorded with a pair of identical microphones positioned at strategic symmetrical positions, such as on opposite sides of the orches The two resulting independent signals L and R are usually treated by a pair of independent channels, including a re-record and the first and second, respectively Playback on various media, broadcast and all forms of playback devices, including load amplifiers and speakers. The basic L and R stereo system is widely used as a standard system in home entertainment systems. Pure L and R signals may be subject to some degree of cross-coupling change in master recording, as well as spatial optimization compensation circuits in small radios and stereo playback devices with built-in stereo speakers with very small pitches.

A alternative stereo recording technique known as "point source stereo" is used two different microphones arranged close together centrally are for usually in the middle and in front of the orchestra: a microphone is omnidirectional and the other bidirectional (also "eighth" or "dipole") directed. The signals from the two microphones, according to the sum (L + R) and the difference + / (L-R) can in two Audio channels be dealt with, but usually in a matrix circuit to process L and R stereo signals for conventional processing through L and R channels to create.

Sum Difference speaker system are not currently for Applications used at a high volume, however, they were for Stereos for the home entertainment proposed, the one radiating forward Speakers and a dual side-emitting dipole speaker use, which are controlled accordingly by summation and difference signals which are derived by matrix mapping of normal L and R stereo signals.

DESCRIPTION OF THE RELATED STATE OF THE ART

The U.S. U.S. Patent 3,588,355 to Helm discloses a stereophonic system with speakers arranged at right angles to each other are received and matrixed sum and difference signals.

The U.S. U.S. Patent 4,819,269 to Klayman discloses an expanded one imaging split-mode speaker system, the sum and difference signals receives.

The U.S. U.S. Patent 5,109,416 to Croft discloses a side-emitting device Dipole speaker receiving a difference signal, and the speaker in conjunction with conventional Direct path speakers can be used to surround sound to produce sound in multiple channels.

The document US3637938 shows a stereo speaker assembly and circuit, wherein a forward-facing speaker and a side-facing dipole speakers are mounted in a common support structure. Incoming "left" and "right" signals are amplified and transmitted to the loudspeakers, the latter being connected via a transformer so that the sum of the amplified left and right signals is formed and fed to the forward facing loudspeaker, and the difference between formed the amplified left and right signals and the sideways directed dipole speaker is supplied.

The document DE3127478 relates to a radio or TV set, wherein sum and difference signals of the stereophonic "left" and "right" signals are obtained directly from a tone decoder, the sum and difference signals being separately amplified and transmitted to a forward-facing speaker / dipole speaker unit become.

TASKS OF INVENTION

Of the The present invention is based on the primary object, in particular for live musical lectures on electronic increased Instruments such as keyboards and electric guitars an electro-acoustic CPS system (CPS as English abbreviation of Center Point Stereo) to provide the musical source signal from the line level output the instrument is processed and acoustically transformed so that stereophonic sound images or sound images are generated from the two speaker units emerge, which together at a central Point of the CPS system are arranged to make live music lectures with stereo effects to improve.

Of the The present invention is based on the further object, a to provide a precise circuit arrangement of a CPS processor, the an optional subwoofer line level output for carrying out the present invention having.

Of the The present invention is based on the further object of several practical implementations of a dipole speaker unit for implementing the To provide invention.

The present invention is based on the further object of the above-described To provide features of the primary object in a minimalist electroacoustic accessory unit, which allows the implementation of the invention with maximum use of commercially available electronic equipment that may already be available to a musician.

Of the The present invention is based on the further object of a completely electro-acoustic embodiment to reveal, with a sound processor, amplifiers and a speaker system from two units that over a line level output or line level output of an instrument works, making stereo sound images to enhance musical Live Presentations be generated.

Of the The present invention is based on the further object, the other Integration of additional Skills for stereo effects such as FX and DSP, for which hardware in the trade available can be.

Of the The present invention is based on the further object, a rack-mountable, individual housing unit providing CPS processing, Special effects such as FX (music effects, usually analog effects) or DSP (digital signal processing), amplification and speaker units having the entire CPS system with its Schallabstrahlern is provided in a single unit.

Of the The present invention is based on the further object of several to provide alternative practical CPS systems for the practice of the invention.

SUMMARY THE INVENTION

In a basic unit comprises the electroacoustic element of the system according to the invention in addition to a front-facing speaker unit, which is itself to an existing, conventional Unit can act with one speaker or multiple speakers connected to swing together, a dipole speaker unit with one or more vertically mounted speakers, the are connected so that they swing together, and where they are aligned are that they have an acoustic field with a double-circle dipole pattern radiate; wherein a pair of side lobes on opposite Pages with opposite polarity is addressed.

The Unit further includes a sum / difference processor of the present invention Invention with L and R stereo audio line inputs for connection to stereo line outputs of Instruments of the artist on, and with a first pair of line outputs that provides: (1) a signal input "sum" in a first Power amplifier, which controls the front-facing speaker unit, that an acoustic field "sum" is emitted; and (2) a signal input "difference" to a second one Power amplifier, which drives the dipole speaker unit which outputs the acoustic field "difference" with the dipole pattern described above radiates.

The Combination of the above sum / difference processor and the associated dipole speaker system for purposes of music performance in accordance with the present Invention is referred to in the market as CPS (Center Point Stereo), from Center Point Stereo, Sylmar, California, USA, partner of the inventors of the present invention, and as SFX (Stereo Field Expander) Fender Musical Instruments Corporation, Scottsdale, Ariz., USA.

The embodiment the unit or the housing can be extended so that it before the CPS processor a commercial stereo FX or DSP unit that produces stereo line outputs: these are usually so designed that over the mono or stereo line input operated the musical instrument.

To the other possible embodiments as a unit or as a housing counting one or both power amplifiers, Woofer speaker units and associated power amplifiers, preamps and Equipment.

SHORT DESCRIPTION THE DRAWINGS

These and other objects, features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings better understandable. In the drawings show:

1 FIG. 4 is a pictorial diagram of an illustrative basic embodiment for carrying out the Center Point Stereo System (CPS) according to the present invention in a typical music lecture environment; FIG.

2 a functional block diagram of the subject matter 1 ;

the 3 to 7 functional block diagrams of alternative embodiments in which the CPS can be carried out according to the present invention, derived from the basic embodiment of the 1 to 2 ;

8th a schematic diagram of the CPS processor unit from the pictures of 1 . 2 and 4 to 7 ;

8A a schematic diagram of a power supply for the CPS processor 8th ;

the 9 . 9A and 9B three views of a first implementation of a dipole speaker unit in conjunction with which the present invention may be practiced using a single loudspeaker mounted on a central baffle;

10 a front view of a second implementation of a dipole speaker unit, in connection with which the present invention can be carried out, using a pair of speakers, which are mounted front to front on a central baffle;

the 11 . 11A and 11B three views of a third implementation of a dipole speaker unit in connection with which the present invention may be practiced using a pair of speakers mounted side by side on a central baffle;

the 12 and 12A two views of a fourth implementation of a dipole speaker unit, with which the present invention can be carried out, using a pair of speakers, which are mounted on opposite side walls of a skirt;

13 a pictorial diagram of a CPS system in relation to the picture 5 using a front-facing, commercially available mono-amplifier-speaker combination for guitars in the sum channel;

14 a pictorial block diagram of a CPS system in relation to the picture 5 with a front view of a three-unit speaker stack with a modular subwoofer speaker unit added under the dipole speaker unit and the front-facing speaker unit; and

15 a pictorial block diagram of a mounted in a rack CPS system via a stereo source as in 4 operated, but otherwise essentially all the components 14 in a single stack.

PRECISE DESCRIPTION THE INVENTION

The picture out 1 Illustratively illustrates a preferred embodiment of the present invention. A music signal source 10 which provides L and R stereo signals according to the display at the audio line outputs, represents virtually any conventional musical instrument such as an "electric" guitar with one or more side pickups, an acoustic guitar or a piano with microphone, a guitar or keyboard controlled Synthesizer or tone generator, which is usually already owned and operated by the musician / user, Such instruments generally provide stereo output signals L and R, which are normally directed in two independent channels that lead to left and right speakers via stereo amplifiers ,

The Terms L and R refer primarily to the perception of the physical relationship in the final sound reproduction. Respect to music source signals L and R partly positions of different instruments and / or various artists, where, in most cases, including of the present text, L and R are not necessarily left / right Affecting relationship at the source, as the two channels are often synthetic generated and / or arbitrary be designated.

In the picture off 1 The signals L and R are the input of the CPS processor 12 (CPS as an abbreviation for Center Point Stereo), wherein the stereo signals L and R are matriziert in such a way that a first line output sum signal s = L + R is provided, ie the sum of the two input signals, and so that a second line output difference signal d = LR is provided, ie the difference between the two input signals.

The sum signal s is passed through the power amplifier 14A amplifies, which generates an amplified sum signal S, which is a conventional, forward-facing speaker unit 16 from which an acoustic field L + R exits in a general forward direction, as shown by the arrow.

Similarly, the difference signal d will pass through the power amplifier 14B amplified, and the amplified difference signal D is the dipole speaker unit 18 which emits acoustic signals from both sides as follows: RL on one side and LR on the other side, so that they are emitted exactly opposite to each other.

The difference acoustic fields LR and RL from the dipole speaker unit 18 The audience will primarily receive space or other ambient reflections while the humming acoustic field R + L from the front-facing speaker unit 16 the listeners arrive mainly in a direct path: these two fields add algebraically to the listener's ear, creating a perception of the intended relationship between L and R.

The gain of the summing amplifier 14A can be adjusted to provide a desired base level of loudness, with the gain of the differential amplifier 14B can be subsequently controlled to provide a desired level of stereo effect, monofonous over a state of normal stereo separation, such as that at the source 10 is present, to a state of exaggerated stereo separation. This control is usually done in such a way as to achieve optimal compensation with respect to the influence of the room or auditorium acoustics.

The dipole speaker 18 and the CPS processor 12 in which it is in the picture 1 The non-conventional components represented by solid lines may be offered as a basic accessory package for musicians who already have the conventional components represented by dashed lines: the source 10 , the amplifier 14A and 14B and the front-facing speaker unit 16 ,

The speaker 18 is shown in the picture by a rectangular box 22 or a rectangular box, which may be merely a speaker stand, which serves to raise the speaker units to an appropriate listening height, but may also be a woofer speaker unit that handles the bass portion of the music in a substantially monophonic manner separate from the stereo mid-tone component.

While a conventional Stereo system for Requires physically separate L and R speakers, generates the present dipole speaker system using mainly reflected paths for the laterally directed difference signals the perception of stereo sound for listeners in the Room or auditorium, with all speakers in the system of Musicians are arranged close together, usually one central Stack and with even combination in a common enclosure, with a wide cover over the large part or the entire room or auditorium is provided, this being an acoustically interactive role in the generation of perception of the stereo music effect.

For one Keyboard player or guitarist is the ability of stereo power, as this is provided by the CPS system, with all speaker units stacked in one position, a distinct advantage in combination with soundstage setup scenarios for live demonstrations. Through the others potential improvement of a more consistent coverage of the auditorium The CPS motivates the player to unlock the potential of the game Live presentation of the stereo skills exploiting this more fully in an electronic instrument is present or can be easily added to this.

The picture out 2 FIG. 12 is a functional block diagram of the preferred embodiment shown in FIG 1 is depicted.

The pictures of the 3 to 7 show functional block diagrams of CPS systems of the present invention in various embodiments, which are illustrated with the figures of 1 and 2 have in common: a pair of amplifiers 14A and 14B , which have as inputs a corresponding sum signal s and a difference signal d, as the amplified versions S and D corresponding to a forward-facing sum speaker unit 16 and a side-facing dipole speaker unit 18 be supplied.

The version from the picture 3 Functionally equivalent to the version 2 However, the summation and subtraction sections of CPS processing are performed separately, rather than both in a CPS processor module. If a power amplifier equipped with dual, gain-controlled inputs is available, these can be used to carry out the L + R addition, as in the amplifier 14C is displayed. A minimal CPS processor 12B is required only to execute the subtraction section of CPS processing; thus, the cost of adding a CPS processor function to an existing system can be reduced.

The picture out 3A shows an alternative passive summing circuit that does not require dual amplifier inputs and thus the use of two identical amplifiers 14B with one input: a pair of equal resistors R3 and R4, which are connected to the common terminal as shown, to the single input of the amplifier 14B connected is. An insertion loss of 6 dB in the sum channel must be used when adjusting the gains in the amplifiers 14B for the S / D balance of the overall system.

The picture out 4 shows a higher modification referring to the subject of the figures of the 1 to 3 applicable, with an additional stereo FX unit 20 (Effects) between the source 10 and the CPS processor 12 is arranged. Such FX units are commercially available and provide for special sound processing, such as reverb, flanging effects, delays, echoes and other music effects. There is a trend to digitally implement such FX units using DSP (Digital Sound Processing) to increase the diversity, capabilities and flexibilities of the units.

The picture out 5 shows a version with mono source, which is based on the subject of 2 to 4 is applicable, being a monaural music source 10A only provides a monophonic signal M. Numerous FX units are designed so that they can be operated either via a mono or stereo source, allowing the FX unit 20 accepts a monophonic signal M as input and converts it into a pair of (synthesized) stereo signals supplied as L and R outputs which control the CPS processor.

The picture out 6 shows a version of the item from the illustration 4 where the FX and CPS processing functions are in an individual FX + CPS processing unit 12A which accepts a mono source signal and supplies the signals s and d to the power amplifiers 14B head for.

In the picture off 7 indicates the source 10C an integrated CPS processor running the CPS processor 12 from the pictures of 1 . 2 . 4 and 5 which is located in the housing of a guitar or a keyboard unit, so that the CPS according to the present invention only with the addition of the special dipole speaker unit 18 together with the following conventional components: the amplifiers 14A and the front-facing speaker unit 16 ,

There are several ways to do this, such as a CPS processor 12 from the pictures of 1 . 2 . 4 and 5 and the dipole speaker unit 18 as the two specific building blocks according to the teachings of the present invention can be combined with conventional components, ie the music sound source 10 , the amplifiers 14A and 14B and a forward-facing speaker unit 18 so that functional systems for practicing the present invention are formed. The realization of two particular components of the invention, the CPS processor 12 and the dipole speaker unit 18 , will be described in the text below with reference to the figures of 8th to 12A described in more detail.

The picture out 8th shows a schematic diagram of the CPS processor 12 from the pictures of 1 . 2 . 4 and 5 ,

Four Operational amplifier, OA1 to OA4, lead the addition and subtraction of the audio signals L and R, which are the Input to the jacks J1 and J2 are fed, and so that the Difference signal d at J3 and the sum signal s at J4 provided as line level outputs become. These four operational amplifiers OA1 to OA4 can be replaced by two dual type 4560 integrated circuits (integrated circuits).

The Sum signal s is further provided by a low-pass filter LPF and a Level adjustment potentiometer R23 led to the output jack J5, the thus provides a line output, which is used to control a subwoofer amplifier / speaker system is compensated.

Of the Subwoofer line output is an optional luxury feature that is essential to the basic design of the Invention is not required.

The picture out 8A shows a schematic diagram of a dual regulated power supply for providing DC power to a CPS processor 12 out 8th ,

The picture out 9 shows a front view of a dipole speaker unit 18 with a substantially open housing 24 , The speaker 26 is on a baffle 24A attached, located in the housing 24 located in or near the center of the housing. The front of the case 24 is configured with a large opening through the edge 24B which may be sized to affect the tone distribution depending on the design selected. The speaker 26 is directed to the left in the figure (arbitrarily) so that its forward acoustic waves radiate to the left, and its reflected wave radiates to the right; since these waves are of opposite polarity, the directional pattern inherently corresponds to an "eight," which is indicative of a dipole configuration, such as a dipole antenna, due to the open basket structure of the loudspeaker 26 For example, the sound pressure of the reflected wave directed to the right is substantially equal to the sound pressure to the front and left waves, so that the dipole direction pattern of the "eight" is practically symmetrical, especially in the mid-frequency range used in stereo imaging and spatial illustration plays the most important role.

One Advantage of the CPS system is that a high and / or low Frequency gain slightly by adding a tweeter and / or (sub) woofer exclusively to the forward-looking unit can be implemented while this at conventional RL stereo both channels added be or over an additional central speaker unit with special transition and matrixing can be implemented have to.

The picture out 9A shows a view of the dipole speaker unit 18 out 9 from the right side: the rear view of the baffle 24A attached speaker 26 is visible through a large opening through the edge 24C which is defined in the enclosure 24 is configured.

The picture out 9B shows a plan view of the dipole speaker unit 18 from above: one through the edge 24D defined opening reveals the baffle 24A attached speakers 26 ,

The contours of the mount 24 may be sized to mate with other available speakers or enclosures for equipment, such as for stacking.

The picture out 10 shows a front view of a dual speaker-dipole speaker unit 18A whose functionality is the functionality of the speaker unit 18 from the pictures of 9 to 9B similar is an open case 28 is with a central baffle 28A configured. Instead of a single speaker, however, there are two speakers 26A provided, when viewed through by the edge 28B limited opening is evident that this front to front at a common opening in the central, vertical baffle 28A attached, which is a central axis of the housing 28 Are defined. The two speakers 26A are connected in opposite polarity (in series or in parallel), so that a common movement of the membrane is effected, as shown by the two arrows, so that they work together to provide the same effect as a single membrane; however, their complementary membrane motion serves to compensate for inherent missing linearities of voice coil movement of each loudspeaker 14B Thus, first-class linearity and fidelity are provided.

The picture out 11 shows a front view of a dipole speaker unit 18B whose functionality is the functionality of the units 18 and 18A from the pictures of 9 and 10 similar to that of the housing 30 open and with a central baffle 30A is configured, with the speakers 26B however, on opposite sides of the baffle 30A surface-mounted and pointing in opposite directions, and as viewed from the right in top view 11A , the plan view from above according to the figure 11B is apparent, are the two speakers 26B in an arrangement side by side and offset from each other with opposite orientation.

The category of central sound baffle and open enclosure dipole loudspeaker units according to the examples of the figures of FIGS 10 to 11B can be implemented with any number of additional speakers mounted on the central baffle; usually an even number of loudspeakers are divided into two groups of oppositely-directed loudspeakers arranged in a complementary pattern, all connected to oscillate together.

In In the category with a central baffle, the case can be designed in this way be that it has open areas, as in each or is shown in all of the six field areas; the size and the Position of the openings are assigned in the design so that the sound dispersion is regulated.

The picture out 12 shows a front view of a dual speaker-dipole speaker unit 18C which differs from the above-described open case category as follows: The unit 18C is constructed like a conventional speaker cabinet, with no central baffle or other large openings than the ones directly on the two speakers 26C are assigned, as shown in dashed lines, the back to back on opposite sides of the enclosure 18C are attached.

As in dipole speaker units in general, the speakers are 26C connected with such polarity that causes their membrane to swing together, as shown by the two arrows. This arrangement leads to significantly different operating conditions than those found in conventional loudspeaker surrounds: the state of common swinging tends to build up sound pressure in the surround 18C compensate or eliminate, even if this is designed to be practically airtight.

As with the approach of a dual loudspeaker Chers with a central baffle can be any of the two side speakers 28C be replaced by two or more speakers, usually by smaller versions.

in the Generally can in dipole speaker implementations, including all versions described above, the speakers in one Dipole speaker unit be made identical; they do not generally have low bass frequencies edit, because such much lower frequencies not much contribute to the stereo effect, so the lower frequencies usually on be treated elsewhere in the entire speaker system, such as in a woofer or subwoofer unit as part of the forward directed unit can be produced.

The previous examples of Dipole speaker units, surround openings and speaker openings are shown without cover for clarity of illustration; in actual versions in practice, however, they are generally with a scrim or Covered knit fabric of known type, both to a better To contribute appearance as well as to fulfill protection functions.

The picture out 13 shows a speaker stack with two units with a dipole speaker unit 18 , which is shown as a unit with a speaker, similar to the unit 18 from the pictures of 9 to 9B , The housing of the dipole speaker unit 18 has a modular size and carries a combo amp unit with a front-facing speaker unit 16 through an integrated amplifier unit 14A is controlled. The monophonic input from the musical instrument source 10 is used as input to the amplifier 14A supplied and internally via a line "FX send" to the FX unit 20 which provides L and R stereo line outputs as inputs to the CS processor 12 be supplied.

The output d (difference LR) of the CPS processor 12 becomes the dipole speaker unit 18 fed through the power amplifier 14B as shown below the dipole speaker unit 18 located.

The output s (sum L + R) of the CPS processor 20 becomes the amplifier 14A supplied via a line input "FX feedback".

This arrangement allows the musician with only a monophonic output of the instrument very conveniently using a switch on the amplifier 14A between (a) a regular monophonic system that only the front-facing speaker unit 16 used, and (b) a multifunctional stereophonic system containing the FX unit 20 , the CPS processor 12 and the dipole speaker unit 18 used.

The picture out 14 shows a stack of three speakers with a modular subwoofer unit 38 under the dipole speaker unit 18 , The subwoofer unit 38 is via the power amplifier 40 which is an input from the subwoofer line output of the CPS processor 12 receives.

An input preamplifier 44 containing a monophonic source signal from a musical instrument source 10 receives, the source signal leads to the monophonic line input of the FX unit 20 to their L and R line outputs to the line inputs of the CPS processor 16 be supplied. The line outputs s and d of the CPS processor 16 become the two line inputs of a stereo amplifier 14D fed to the front-facing speaker unit 16 and the dipole speaker unit 18 so that midpoint stereo sound is generated.

The picture out 15 shows a front view of a mounted in a rack system, which is a single tower unit with all components from the figure 13 Provides: Starting from the bottom, it is the subwoofer unit 38 , the dipole speaker unit 18 , the front-facing speaker unit 16 , the subwoofer power amplifier 40 , the CPS processor 12 , the stereo power amplifier 14C , the stereo FX unit 20 and the input preamplifier 44 , The single tower requires only a monophonic music source, such as a guitar or keyboard / tone generator, to provide a complete live lecture operating system that fills an auditorium with stereo sound effects coming directly from the rack as a midpoint source Center point source of the stereo sound.

The Invention may also be embodied in other particular embodiments and be implemented. The present embodiments are thus to interpret in all respects as illustrative and not restrictive, the scope of the present invention is not limited by the above Description is indicated by the appended claims becomes.

Claims (12)

A method of producing musical stereo sound images comprising a live performance of a musical instrument ( 10 ), wherein the sound images by acoustic combination of the two different speaker units ( 16 . 18 ) are arranged together in a listening environment at a center of a CPS system, that is, a centerpoint stereo system, the method comprising the steps of: a) performing music on the musical instrument ( 10 ) so that a multi-component electrical source signal is generated in real time representing the music being played; b) processing the source signal in a manner to generate: 1) a sum signal representing a sum of the two selected component portions of the source signal; and 2) a difference signal representing the difference between the two selected component portions of the source signal; c) amplifying the sum signal in a first power amplifier ( 14A ), so that a power-amplified sum signal is provided; d) amplifying the difference signal in a second power amplifier ( 14B ), so that a power-amplified difference signal is provided; e) supplying the power-amplified sum signal to a front-facing loudspeaker unit ( 16 ) disposed at the center and configured, arranged and oriented to emit a summation sound field in a unidirectional pattern predominantly in a forward direction towards a listening area of the listening environment; f) supplying the power amplified difference signal to a sideways dipole speaker unit ( 18 ), which is also generally arranged together with the front-facing loudspeaker unit at the center, said dipole loudspeaker unit ( 18 ) is arranged, arranged and oriented to emit a difference tone field in a dipole pattern having two oppositely poled beams directed substantially in opposite lateral directions which are perpendicular to the forward direction; wherein an acoustic combination of a summation sound field reaching a listener in the audience area over a predominantly direct path and a difference sound field reaching the listener over a predominantly reflected path is effected so as to cause the listener to perceive stereophonic images, which represent the recited music, which spreads panoramic to the left and right of the common central speaker position. Method for generating musical stereo sound images according to claim 1, wherein step b) comprises the following substeps includes: b1) deriving a left stereo signal and a right stereo signal from the source signal; b2) feeding the left stereo signal and the right stereo signal to a summing circuit, the is designed and arranged to make it a summed signal which represents a sum of the left and right stereo signals; b3) the feeding of the left stereo signal and the right stereo signal to one Subtraction circuit which is designed and arranged such that From this, it generates a difference signal which is a difference between represents the left and right stereo signals. The method of generating musical stereo sound images according to claim 1, further comprising the substeps of: b1) deriving a left stereo signal and a right stereo signal from the source signal; b2) supplying the left stereo signal and the right stereo signal to inputs of a stereo music effects unit ( 20 ) configured and arranged to modify the left and right stereo signals in a predetermined manner, and to provide as output left and right modified stereo signals; b3) supplying the left and right modified stereo signals to a summing circuit configured and arranged to produce therefrom a sum signal representing a sum of the left and right stereo signals; b4) supplying the left and right modified stereo signals to inputs of a subtraction circuit designed and arranged to produce therefrom a difference signal representing a difference between the left and right modified stereo signals. The method of generating musical stereo sound images of claim 1, further comprising the steps of: f) processing the sum signal of step b) with a frequency response modification circuit that attenuates high frequency components of the sum signal to provide a subwoofer signal; and g) supplying the subwoofer signal to a subwoofer speaker unit ( 38 ) via a third amplifier ( 40 ), so that a bass amplification is supplied to the first sound pattern. Stereo center music presentation system for providing a musical stereo sound image via two different types of speaker units ( 16 . 18 ) arranged together at a common center, the system comprising: a musical instrument ( 10 ) configured and arranged to generate in real time an electrical source signal representing music played on the instrument; a sound processing system that uses as input Receiving source signal from said musical instrument, the system being arranged and arranged to derive and generate therefrom: (1) a line level sum signal representing a sum of two selected component portions of the source signal; and (2) a line level difference signal representing the difference between the two selected component portions of the source signal, wherein the two component portions are selected in a manner that enables generation of a desired stereo image from the acoustic new combination of the two component portions; a first sound power amplifier ( 14A ) receiving as input the line level sum signal and providing as output a power amplified sum signal; a second sound power amplifier ( 14B ) receiving as input the line level difference signal and providing as output a power amplified difference signal; a forward looking speaker unit ( 16 ) having at least one vertically mounted loudspeaker driven by the power amplified sum signal, the unit being arranged and aligned to emit sound in a general forward direction; and a sideways dipole speaker unit ( 18 ) having at least one vertically mounted loudspeaker driven by the power amplified difference signal, said sideways dipole loudspeaker unit being arranged and oriented generally perpendicular to said forward looking loudspeaker unit and being configured and arranged such that it emits sound in a dipole pattern, ie, with opposite phase polarity and in opposite lateral directions, generally perpendicular to the forward direction. A stereo center music performance system according to claim 5, wherein said sound processing system comprises: an electronic sound processing module ( 12 ) receiving as input the source signal from said musical instrument, the module being arranged and arranged to produce as outputs the line level sum signal and the line level difference signal. A stereo center music lectern system according to claim 5, wherein said audio processing system comprises: a stereo matrix circuit receiving as input said source signal, said circuit being arranged and arranged to generate a left stereo signal and a right stereo signal from said signal ; and a CPS processor ( 12 ) receiving as input the left and right stereo signals, the processor being arranged and arranged to produce as output the line level sum signal and the line level difference signal. A stereo center music lectern system according to claim 5, wherein said audio processing system comprises: a stereo matrix circuit receiving as input said source signal, said circuit being arranged and arranged to generate a left stereo signal and a right stereo signal from said signal ; a stereo music effects unit ( 20 ) receiving as input the left and right stereo signals, the unit having a configuration and arrangement for modifying at least one signal of the left and right stereo signals in a predetermined manner, and thus a left modified signal and a right modified one Stereo signal are generated; and a CPS processor ( 12 ) receiving as input the left and right modified stereo signals, the processor being arranged and arranged to produce as output the line level sum signal and the line level difference signal. A stereo center music presentation system according to claim 5, wherein said sideways dipole speaker unit ( 18 ) comprises: a rectangular resonance wall ( 24A ) aligned vertically and in a longitudinal direction provided with a generally circular speaker cutout portion; a cone speaker ( 26 ) mounted centrally on a first side of said resonating wall, concentric with the cutout portion; and a substantially open housing ( 24D ) configured as a frame surround completely surrounding said speaker and the resonance wall mounted on said resonance wall. A stereo center music presentation system according to claim 5, wherein said sideways dipole speaker unit ( 18 ) comprises: a rectangular resonance wall ( 28A ) aligned vertically and in a longitudinal direction provided with a generally circular speaker cutout portion; a first speaker ( 26A ) having a cone diaphragm mounted on a first side of said resonance wall concentric with the cutout portion; a second speaker ( 26A ) with a conical membrane attached to a second side of said resonant wall opposite to first side, concentric with the cutout portion, electrically connected in a manner to said first loudspeaker so as to cause vibration of both cone membranes in unison under a controlled condition; and a generally open housing ( 28 ) configured as a frame completely surrounding said speakers and the resonance wall mounted on said resonance wall. A stereo center music presentation system according to claim 5, wherein said sideways dipole speaker unit ( 18 ) comprises: a rectangular resonance wall ( 30A ) aligned vertically and in a longitudinal direction provided with first and second generally circular speaker cut-out portions which are staggered side by side relative to each other; a first speaker ( 26B ) having a cone diaphragm mounted on a first side of said resonance wall concentric with the first cutout portion; a second speaker ( 26B ) having a cone diaphragm mounted on a second side of said resonant wall, opposite the first side, concentric with the second cutout portion and thus directly aligned with said first speaker, electrically connected in a manner to said first speaker such that causing vibration of both cone membranes in unison under a controlled condition; and a generally open housing ( 30 ) configured as a frame completely surrounding said speakers and the resonance wall mounted on said resonance wall. A stereo center music presentation system according to claim 5, wherein said sideways dipole speaker unit ( 18 ) comprises: a generally closed housing ( 18C ) having two opposing parallel fields each configured with a speaker cutout opening; first and second speakers ( 26C ) each having a conical membrane and respectively attached to a corresponding one of the parallel arrays in an acoustic operating relationship with the respective cutout opening, said loudspeakers being electrically connected together in a manner to cause both of them Swing cone cone under a controlled state in harmony.